Briarberry Cohort

The condition is the whole bargain: a 1/1 flier for two mana on its own, a 2/2 flier the moment any other blue creature joins it. No counters to track, no upkeep tax, no decision at any point, just a static state check that reads your own board and resolves the math for you. The discipline is in what triggers the bonus and what doesn't: it cares only about a second blue body, so trading the rest of your creatures into removal leaves you holding a bare evader, while a side of the table that goes wide in one color keeps it pumped almost by default. That makes it self-correcting in multiples, where each copy props up the next and the requirement is met the instant two are down. The faerie tribe matters to the arithmetic too, since the deck that wants several small flying threats is exactly the deck that satisfies the clause without effort. The real work this kind of design does is structural: a small mono-blue body that grows when a second creature of its own color shows up is the cheapest possible nudge toward committing to one color rather than splashing, the sort of low-rarity reward that quietly steepens an aggressive monocolor curve without ever asking the pilot to think about it.